Synthesis of MOF derivatives@3D graphene hybrid materials towards high-performance electrode material for supercapacitors

In this paper, MOF derivatives@3D graphene hybrid materials have been prepared by the electrostatic adsorption of GO and ZIF-8 together with in-situ self-assembly of GO. The hybrid materials are systematically characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscope. The result shows that the obtained hybrid materials have a well-defined and cross-linking porous structure. The MOF-derived particles with diameter of about 100 μm are dispersed in the network structure of 3D graphene. The hybrid materials as electrode exhibit good specific capacitance of 214 F/g (0.5 A/g), superior to the individual graphene (171 F/g) and MOF derivatives electrode (104 F/g). Furthermore, an asymmetric supercapacitor has been developed using MOF derivatives@3D graphene hybrids as positive electrode and graphene aerogel as negative electrode in 6 M KOH electrolyte. Due to the excellent structure of hybrid materials, asymmetric device could be reversibly cycled in the voltage range of 0–1.6 V, and exhibits a maximum energy density of 22.4 Wh/kg for a power density of 160 W/kg. The excellent electrochemical properties indicate that the obtained hybrids are expected to become potential electrode material for practical applications.